Motor vehicle driving mechanism



Dec. 15, 1942. A. M. woLF Re. 224,236

MOTOR VEHICLE `DRIVING MEGHANISM Original Filed April 9, 1936 2 Sheets-Sheet l 60 68 ,9 O -u 6 O 'f3 A INVENTOR. .72 Mrz/.7%. l/Ifa Y ATTORNEY.

Dec. 15, 1942. v v A. M. WOLF Re. 22,236

MOTOR VEHICLE DRIVING MECHANISM Original Filed April 9, 1936 2 Sheets-Sheet 2 INVENT OR.

ATTORNEY.

Reissued Dec. 15, 1942 Original No. 2,238,615, dated April 15, 1941, Serial 1 No. 287,704, August 1, 1939, which is a division of Serial No'. 73.584, AprilA 9, 1936, which isl a continuation oi' Serial No. 612,057, May 18, 1932. Application for reissueFebruary 4, 1942 Serial 8 Claims. (C1. 18o-54) tween said mechanism and the respective engines.

'I'his invention relates to motor vehicle driving mechanism, the subject matter of the present f application constituting. a division of my pending application fon patent Ser. No. 73,584 filed April 9, 1936, which in turn is a Acontinuationof my original application Ser. No. 612,057 filed vMay 18, 1932.

Generically considered, it is `the primary object and purpose of the present invention to provide a simply constructed and eiiiciently operating unitary power plant and variable speed transmission mechanism, embodying one or more engines or prime movers and which may be readily mounted in a minimumof space transversely of the vehicle frame or chassis and in' closely spaced relation to one of the vehicle axles.

It is a more particular object of the invention, in one embodiment thereof, to provide in combination with 'differential axle drive mechanism and propelling means therefor, a power plant forming a part of the sprung weight of the vehicle and embodying an engine, clutch and clutch driven power transfer means arranged transversely of the vehicle, said power transfer means including power input and output shafts, one of which is tubular and surrounds the other in coinciding axial relation therewith, and means for transmitting power from the engine through said power transfer means to the differential embodying a power transmitting member fixed to said power output shaft. i

In one embodiment of the invention, the engine is arranged transversely of the vehicle at one side of its centerline and a variable speed transmission mechanism is mounted within a suitable housing rigidly connected with the inner end of the engine while the power transmitting clutch is interposed between said mechanism and the engine crank shaft. I further propose to provide such arrangement at the rear end of the vehicle in closely coupled relation with the differential drive mechanism for the rear axle and with said power transmission mechanism disposed at right angles to the engine crank shaft and in rearwardly projecting relation thereto, or in parallel relation with the crank shaft.

It is a further object of the invention to provide a dual engine power plant in which two transversely positioned engines are arranged in balanced relation at opposite sides of the propelling connection with the rear axle differential and in which a single variable speed transmission mechanism may be selectively coupled with the crank shafts of the respective engines by independently operable clutches interposed be- Other objects ofvmy inventionreside in the provision` of independently mounted rear wheel `axles with a unitary constructionof the diil'erential and transmission housings, or a vclosely coupled `relatively movable connection kbetween the differential and transmission housing.

Withl the above and other objects in view the invention `consists inthe limproved motor vehicle driving mechanism, and in the form, construction and relativev arrangement of its several parts'v as will hereinafter be more fully described, illustrated in the accompanying drawings andA subsequently incorporated inv the suhjoined claims.

In the drawings wherein I have shown several simple and practical embodiments of the invention and in which similar reference characters designate corresponding parts throughout the several views:

Fig. 1 is a side elevation, partly in section, of a motor vehicle bus or coach showing the power plant mounted at the front end of the vehicle and having a driving connection with the rear axle differential mechanism.

Fig. 2 is a fragmentary bottom plan view showing the power plant mounted at the rear end of the vehicle in closely coupled relation with the differential drive for the rear axle.

Fig. 3 is a similar view of the power plant, the housing for the power-transmission gearing being shown in section.

Fig. 4 is a view similar to Fig. 2 on an enlarged scale illustrating a modified construction.

Fig. 5 is a longitudinal section taken on the line 5-5 of Fig. 4.

Fig. 6 is a sectional view showing a unitary construction of the transmission and differential housing and a modiiied form of the propelling means, and

Fig. '7 is a plan-view illustrating the independently mounted rear wheel axles and another alternative unitary construction of the differential and transmission housing. n v

Referring in detail to the drawings, in Fig. l thereof I have shown the combined power plant and variable speed transmission unit as applied toA a vmotor coach or bus, although it will be understood, as the description proceeds, that my invention is applicable as well to various other standard types of commercial and pleasure vehicles. Y i

The body 5 of thev vehicle is supported by any conventional suspension system upon the front and rear axles 6 and 'l respectively and at its front end is provided with the drivers seat 8 .comprises one or more engines positioned in cylinder size. Furthermore such small engines are behind the steering wheel 8. The power plant advance of and in closely spaced relation to the front vehicle axle 6, said engine or engines being mounted in any Vapproved manner transversely of the vehicle frame or chassis and constituting a part of the sprung weight of the vehicle. In Fig. l the combined engine and transmission unit is shown behind the radiator i0, the power output shaft o! the transmission mechanism being connected by the propeller shaft, indicated at Il,

with the differential drive mechanism of the rear axle 1. As herein shown, the front wall of the .vehicle body 5 in which the usual windshield is provided.. slopes downwardly, as at I2, and merges into the top wall of the engine compartment. This arrangement provides, in a vehicle of minimum over-all length, maximum passenger carrying capacity.

For the operationo! trucks. buses and other relatively heavy commercial vehicles, I prefer to use two standard engines of normal size in the power plantto obtain the required power output, instead of a single engine of abnormally large readily obtainable at comparatively low cost and also due to the use of a greater number of small cylinders a more uniform power flow wouldbe obtained.

As shown in Figs. 2 and 3, the pair of engines I3 and I4 are positioned transversely of the vehicle body with their crank shaft axes in alignment. In Fig. 2 of the drawings I have shown the alternative arrangement of the power plant in rearwardly spaced relation from the rear vehicle axle and extending across substantially the entire width of the vehicle. This arrangement permits of the use of a relatively short propeller shaft I5 or other equivalent driving connection between the power transmission mechanism and the differential drive of the rear axle.

Each of the engines I3 and I4 is provided with a-flywheel I5, I1 at the inner end of its crank shaft with which'suitable clutch means I8, I9 coacts to transmit power to the beveled gears 2li, 2| fixed to the driven clutch shafts 22 and 23 respectively. Ihe engine clutches and power transfer gearing is enclosed within the housing 24 which is rigidly ixed in any suitable manner to the opposed ends of the spaced engines I3 and I4 and is provided with a lateral extension 25 housing the variable speed transmission gearing to be presently described. As shown in Fig. 2 of the drawings, lwhen the power plant is installed behind the rear axle of the vehicle, the transmisy .sion gearing with its housing 25 extends at right angles to the engine crank shafts and rearwardly thereof.

In the embodiment of thetransmission gearing which I have selected for illustration, the same includes a tubular power input shaft 25 having the beveled gear 21 at one end thereof in constant mesh with gears 20 and 2 I At its other end said tubular shaft 2G is also provided with the gear 2B in constant mesh with gear 29 fixed to one end of the countershaft 30. This shaft carries spaced gears 3| of different diameters for engagement by the shiftable variable speed gears 32 splined upon the power output shaft 33. This shaft extends through the tubular power input 70 shaft 26 to rotate relative thereto and projects exteriorly of the housing 24. The propeller shaft I5 is connected by the usual flexible connections or universal joints indicated at 34, with the end of the shaft 33 and the driving member of the diiier- 75 combined power plant and transmission is mounted at the front end of the vehicle it will be understood that the transmission and its housing 25 projects forwardlywithin the engine compartment from the engines I3 and I4.

From the above description, it will be seen that I have provided a simple space conserving mounting and arrangement of the dual engine power plant and variable speed transmission, and in which power losses between the engine crank shaft and the ilnal di'erential drive will be reduced toa minimum. Also by means vof theindependently operable clutches IB and I9, the engines may beselectively coupled with the transmission unit and the vehicle driven by a single engine, should Athe other become disabled, or when carrying light loads. When the full power output of both engines is required the combined power output thereof is transmitted through said clutches tothe single compactly arranged variable speed transmission mechanism.

`In Figs. 4 and 5 of the drawings, I have illustrated an alternative arrangement of the variable speed transmissionmechanism with respect to the engines, in which the power input and output axes disposed in parallel relation with the engine f crank shafts. In this case, the engines, ilywheels and clutches are provided as above described, but

the power is transmitted from the clutches through a common power-.input shaft 36.

Gear 31 fixed to the shaft near one of its ends is in constant mesh with a mating gear 3B on a countershaft 39. Additional gears of relatively different diameters, as indicated at 40, are also fixed tothis countershaft to mesh with the sliding gears 4I and 42 respectively on the tubular power output shaft 43 which surrounds the power input shaft 35 in spaced relation thereto. beveled gear44 is fixed to the shaft 43 at its approximate center and is in constant mesh with the beveled pinion 45 on the shaft 4'6. This latter shaft is disposed on the longitudinal center line of the vehicle and'is suitably mounted in one side of the housing 41 which encloses the above described transmission gearing and has end extensions, enclosing lthe fiywheels I'5-I1, fixed to the inner ends of the respective engines I3 and I4. A longitudinally disposed propelling shaft 48 has universal joint connections at its opposite ends with the shaft 48 and the differential drive mechanism 49 of the rear vehicle driving axle 50.

lIt will be understood from the above description that the countershaft 39 constitutes an intermediate power output shaft between the input shaft 35 and the final power output shaft 43, all of said shafts being disposed in parallel relation with the axis of the engine crank shaft.

In Fig. 6 of the drawings I have illustrated an alternative of the propelling means shown in Fig. 4, in which said propelling connection between the power output shaft and the differential is in the form of an endless sprocket chain 5I. It will, however, be understood that if desired a gear train or other well known equivalent power 'transmitting connection between the transmission and dierential maybe employed. In this case, the differential and sprocket chain are enclosed within a housing 52 having a neck extension 53 projecting rearwardly therefrom and provided with spaced anges 54 and 55 respectively having sliding bearing engagement with inner and outer nished surfaces of the wall of the transmission housing 41. 'Ihe housing wall is provided with a vertically extending slot G which permits the differential and transmission housings to have relative vertical sliding l'movement in curved path concentric with the engine crank shafts. The flanges 54 and 55 provide an oil tight Joint between the two housing sections. This arrangement in eiect provides a unitary housing structure for the transmission and differential which is secured to and supported by the inner ends of the engines or motors I3 and I4.

In the drawings I have Yshown the power plant and vehicle drive mechanism mounted in rearwardly spaced relation from the rear vehicle axle. It will, however, be apparent that the power plant might be mounted in advance of said axle, or may be similarly arranged with relation to the front .vehicle axle with the conventional driving connections to the dierential of the rear axle. Also, where space conditions permit, the transversely distributed motor or engine and driving units may be mounted -directly above the rear vehicle axle, in which case, of course, the propelling connection between the transmission and the differential will be vertically positioned instead of horizontally as shown in the drawings.a

In Fig. 7 of the drawings I show another modification in which the transmission housing 41' flxed to the inner ends of the spaced engines has anl integral extension 6U which is also formed integral with the housing 6I for the final differential drive mechanism. In this case therefore,

wheels 62, 63 are mounted on independent axles 64, 65 respectively. These axles at their inner ends are pivotally mounted on the diiferential housing, the pivot connections 6B and 61 respectively being located on the center lines of the universal joints 68, 69 which convey power from the differential to the respective wheels through the axles 64, G5. This arrangement allows for the relative vertical movement of said axles and the wheels 62 and 63.

While I have above described and illustrated in the accompanying drawings several concrete examples of practical embodiments of the invention, it is nevertheless to be understood that in each of the disclosed constructions, the combination construction and relative arrangement of the various elements are susceptible of more or less modification. Accordingly, this invention is not to be limited in these particulars, since it may also be exemplified in various other alternative structural forms not herein specifically disclosed, but which may be fairly comprehended as within the spirit and scope of the appended claims.

I claim:

1. Motor Vehicle driving means including a' pair of engines transversely positioned in spaced apart relation in the vehicle frame and arranged in spaced relation to the differential axle drive mechanism, a variable speed transmission mechanism including a power input shaft, housing means therefor interposed between and rigidly connected with the inner ends of said engines, independently operable clutches in coaxial relation with said power input shaft for selectively coupling the opposite ends of said shaft with the respective engine crank shafts, and -propelling means connecting said transmission mechanism with the differential drive mechanism.

2. Motor vehicle driving means including the rear axle differential mechanism, an engine mounted in a transverse position in the vehicle frame and rearwardly spaced from said diiferential mechanism, variable speed transmission mechanism and housing means therefor rigidly mounted on one end of the engine and in longitudinal alignment with the diiferential mechanism.' said transmission mechanism being axially disposed at right angles to the engine crank shaft and extending rearwardly therefrom, clutch means for drive connecting the engine crankshaft with'said transmission mechanism, and propelling means between the transmission mech anism and the diiferential drive mechanism.

3. Motor vehicle driving means including rear axle differential drive mechanism, an engine transversely positioned in the vehicle frame in rearwardly spaced relation from the differential mechanism, variable speed transmission means and aclutch for drive connecting the same with the engine crank shaft, housing means for said transmission means and clutch rigidly ilxed to one end of the engine, saidtransmission means comprising power input and output shafts axially disposed at right angles to the engine crank shaft and extending rearwardly therefrom, and a propeller shaft operatively connecting said power output shaft with the differential drive means.

4. In a motor vehicle, a pair of transversely positioned engines, spaced apart on opposite sides of' the vehicle center line, variable speed mechanism arranged between said engines and in substantially parallel relation to one of the vehicle axles, and clutch means for selectively connecting said variable speed mechanism with the respective engines, said mechanism including power output and input shafts in axial alignment with the engine crank shafts, one of said shafts being tubular and surrounding the other in spaced relation thereto, and means for transmitting power from the output shaft to the vehicle axle.

5. Motor vehicle driving means including an engine mounted in a transverse position in the vehicle frame at one side of the longitudinal center line thereof, differential drive mechanism longitudinally spaced from the engine at the center line of the vehicle frame, and means for transmitting power from said engine to the differential drive mechanism, comprising a power input shaft and clutch drive connected in axial alignment with the engine crank shaft, a tubular shaft surrounding and spaced from said input shaft and drive connected at one of its ends therewith, means operatively connectingl said tubularl shaft with said differential drivemechanism, and a transmission and differential housing secured to the inner end of said engine and positioned in. the longitudinal center line of the vehicle frame.

6. In a motor vehicle construction, a transversely disposed power plant occupying substantially the entire width of the vehicle and including an engine and a clutch arranged in axial transverse succession, power transmitting mechanism including a differential axle drive mechanism and a change speed mechanism arranged in substantially longitudinally aligned succession with respect to each other, power transmission means between the clutch and change speed mechanism, and propelling means connecting the change speed mechanism with the differential drive mechanism.

'1. In a motor vehicle, a body, a pair of transversely spaced supporting wheels for said body and transverse drive axles for the wheels, power transmitting mechanism associated with the axles including, in longitudinal succession, differential mechanism connecting the drive axles, variable speed mechanism, and a power plant 4 v nasse unit including an engine and a clutch disposed transversely of the vehicle body', housings for the diiferential mechanism and the variable speed mechanism, one oft said housings having a lateral extension directly connected with the other housing. propelling means connecting the diiferential mechanism with the variable speed mechanism I and extending through said housing extension, and means operatively connecting the engine clutch with the variable speed mechanism.

8. Motor vehicle driving means including an engine mounted in a transverse position in the vehicle frame at one side of the longitudinal center line thereof, dinerential drive mechanism l longitudinally spaced from the'engine, and means for transmitting power from said engine to the differential drive mechanism comprising a power input shaft, a clutch drive connecting said input shaft with the engine crank shaft, a tubular shaft surrounding and spacedd'from said input shaft and drive connected at one of its ends therewith, means operatively connecting said tubular shaft with said differential drive mechanism', and a transmission and differential housing secured to the inner end o! saidl engine.

AUSTIN M. WOLF. 

